Vehicle, method of controlling vehicle, and vehicle control interface box

ABSTRACT

An ADS performs processing including setting an initial value of a wheel steer angle command when an autonomous state has been set to an autonomous mode, obtaining a limitation of a rate, setting a wheel steer angle limitation as the wheel steer angle command when magnitude of the initial value is larger than the wheel steer angle limitation, and transmitting the wheel steer angle command.

This nonprovisional application is based on Japanese Patent Application No. 2021-157625 filed with the Japan Patent Office on Sep. 28, 2021, the entire contents of which are hereby incorporated by reference.

BACKGROUND Field

The present disclosure relates to control of a vehicle during autonomous driving.

Description of the Background Art

An autonomous driving system for controlling a vehicle to travel without requiring an operation by a user has recently been developed. For being mountable on an existing vehicle, the autonomous driving system may be provided, for example, separately from the vehicle with an interface being interposed.

For example, Japanese Patent Laying-Open No. 2018-132015 discloses as such an autonomous driving system, a technique that allows addition of an autonomous driving function without great modification to an existing vehicle platform, by providing an electronic control unit (ECU) that manages motive power of a vehicle and an ECU for autonomous driving independently of each other.

SUMMARY

In control of a steering angle in accordance with a request during autonomous driving of a vehicle, when the steering angle abruptly changes with sudden increase in requested amount of the steering angle, stability of the vehicle may become poor.

An object of the present disclosure is to provide a vehicle on which an autonomous driving system is mountable, a method of controlling a vehicle, and a vehicle control interface box that allow improvement in stability of steering during autonomous driving.

A vehicle according to one aspect of the present disclosure is a vehicle on which an autonomous driving system is mountable. The vehicle includes a vehicle platform that carries out vehicle control in accordance with a command from the autonomous driving system. The vehicle platform includes a base vehicle and a vehicle control interface box that interfaces between the autonomous driving system and the base vehicle. From the autonomous driving system to the base vehicle, a wheel steer angle command that requests a steer angle of a steering wheel is transmitted through the vehicle control interface box. From the base vehicle to the autonomous driving system, a signal indicating the steer angle is transmitted. The steer angle requested in the wheel steer angle command is set not to exceed a restriction range of a rate of the steer angle that is set based on a velocity of the vehicle.

Thus, the wheel steer angle command is set not to exceed the restriction range of the rate of the steer angle. Therefore, even when a requested amount of the wheel steer angle of the steering wheel suddenly increases, abrupt change in steering angle is suppressed. Therefore, degradation of stability of the vehicle can be suppressed.

In one embodiment, the restriction range is set such that magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a first velocity is smaller than magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a second velocity lower than the first velocity.

Thus, since magnitude of the upper limit value of the rate of the steer angle is smaller as the velocity of the vehicle is higher, abrupt change in steer angle is suppressed. Therefore, degradation of stability of the vehicle can be suppressed.

A method of controlling a vehicle according to another aspect of the present disclosure is a method of controlling a vehicle on which an autonomous driving system is mountable. The vehicle includes a vehicle platform that carries out vehicle control in accordance with a command from the autonomous driving system. The vehicle platform includes a base vehicle and a vehicle control interface box that interfaces between the autonomous driving system and the base vehicle. The method includes transmitting a wheel steer angle command that requests a steer angle of a steering wheel from the autonomous driving system to the base vehicle through the vehicle control interface box, transmitting a signal indicating the steer angle from the base vehicle to the autonomous driving system, and setting the steer angle requested in the wheel steer angle command not to exceed a restriction range of a rate of the steer angle that is set based on a velocity of the vehicle.

In one embodiment, the restriction range is set such that magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a first velocity is smaller than magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a second velocity lower than the first velocity.

A vehicle control interface box according to yet another aspect of the present disclosure is a vehicle control interface box that interfaces between an autonomous driving system and a vehicle on which the autonomous driving system is mountable, the vehicle including a vehicle platform that carries out vehicle control in accordance with a command from the autonomous driving system. The vehicle platform includes a base vehicle. The vehicle control interface box transmits a wheel steer angle command that requests a steer angle of a steering wheel from the autonomous driving system to the base vehicle. The vehicle control interface box transmits a signal indicating the steer angle from the base vehicle to the autonomous driving system. The steer angle requested in the wheel steer angle command is set not to exceed a restriction range of a rate of the steer angle that is set based on a velocity of the vehicle.

In one embodiment, the restriction range is set such that magnitude of an upper limit value of the rate when the velocity of the vehicle is set to the first velocity is smaller than magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a second velocity lower than the first velocity.

The foregoing and other objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of the present disclosure when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing overview of a vehicle according to an embodiment of the present disclosure.

FIG. 2 is a diagram illustrating in detail, a configuration of an ADS, a VCIB, and a VP.

FIG. 3 is a flowchart showing exemplary processing for setting a reference value performed in the ADS.

FIG. 4 is a flowchart showing exemplary processing performed in the ADS in an autonomous mode.

FIG. 5 is a diagram showing in a table format, relation between a vehicle velocity and a wheel steer angle rate limitation.

FIG. 6 is a map showing relation between a vehicle velocity and a wheel steer angle rate limitation.

FIG. 7 is a flowchart showing exemplary processing performed in the VCIB.

FIG. 8 is a diagram showing an overall structure of an Autono-MaaS vehicle.

FIG. 9 is a diagram showing a system architecture of the Autono-MaaS vehicle.

FIG. 10 is a diagram showing a typical workflow in the ADS.

FIG. 11 is a diagram showing relation between a front wheel steer angle rate limitation and a velocity.

FIG. 12 is a state machine diagram of the power mode.

FIG. 13 is a diagram showing details of shift change sequences.

FIG. 14 is a diagram showing immobilization sequences.

FIG. 15 is a diagram showing standstill sequences.

FIG. 16 is a state machine diagram of an autonomy state.

FIG. 17 is a diagram showing an authentication process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present disclosure will be described below in detail with reference to the drawings. The same or corresponding elements in the drawings have the same reference characters allotted and description thereof will not be repeated.

FIG. 1 is a diagram showing overview of a vehicle 10 according to an embodiment of the present disclosure. Referring to FIG. 1 , vehicle 10 includes an autonomous driving kit (which is denoted as “ADK” below) 200 and a vehicle platform (which is denoted as “VP” below) 120. ADK 200 and VP 120 are configured to communicate with each other through a vehicle control interface.

Vehicle 10 can carry out autonomous driving in accordance with control requests (commands) from ADK 200 attached to VP 120. Though FIG. 1 shows VP 120 and ADK 200 at positions distant from each other, ADK 200 is actually attached to a rooftop or the like of a base vehicle 100 which will be described later. ADK 200 can also be removed from VP 120. While ADK 200 is not attached, VP 120 can travel by driving by a user. In this case, VP 120 carries out travel control (travel control in accordance with an operation by a user) in a manual mode.

ADK 200 includes an autonomous driving system (which is denoted as “ADS” below) 202 for autonomous driving of vehicle 10. For example, ADS 202 creates a driving plan of vehicle 10 and outputs various commands (control requests) for travel of vehicle 10 in accordance with the created driving plan to VP 120 in accordance with an application program interface (API) defined for each command. ADS 202 receives various signals indicating statuses (vehicle statuses) of VP 120 from VP 120 in accordance with the API defined for each signal and has the received vehicle status reflected on creation of the driving plan. A detailed configuration of ADS 202 will be described later.

VP 120 includes base vehicle 100 and a vehicle control interface box (which is denoted as “VCIB” below) 111 that implements a vehicle control interface provided within base vehicle 100.

VCIB 111 can communicate with ADK 200 over a controller area network (CAN). VCIB 111 receives various commands from ADK 200 or outputs a status of VP 120 to ADK 200 by executing a prescribed API defined for each communicated signal. When VCIB 111 receives a control request from ADK 200, it outputs a control command corresponding to the control request to a system corresponding to the control command through an integrated control manager 115. VCIB 111 obtains various types of information on base vehicle 100 from various systems through integrated control manager 115 and outputs the status of base vehicle 100 as the vehicle status to ADK 200.

VP 120 includes various systems and various sensors for controlling base vehicle 100. As VP 120 carries out various types of vehicle control in accordance with a control request from ADK 200 (more specifically, ADS 202), autonomous driving of vehicle 10 is carried out. VP 120 includes, for example, a brake system 121, a steering system 122, a powertrain system 123, an active safety system 125, and a body system 126.

Brake system 121 is configured to control a plurality of braking apparatuses provided in wheels of base vehicle 100. The braking apparatus includes, for example, a disc brake system that is operated with a hydraulic pressure regulated by an actuator.

For example, wheel speed sensors 127A and 127B are connected to brake system 121. Wheel speed sensor 127A is provided, for example, in a front wheel of base vehicle 100 and detects a rotation speed of the front wheel. Wheel speed sensor 127A outputs the rotation speed of the front wheel to brake system 121. Wheel speed sensor 127B is provided, for example, in a rear wheel of base vehicle 100 and detects a rotation speed of the rear wheel. Wheel speed sensor 127B outputs the rotation speed of the rear wheel to brake system 121. Wheel speed sensors 127A and 127B each provide a pulsed signal as an output value (a pulse value). The rotation speed can be calculated based on the number of pulses in the pulsed signal. Brake system 121 outputs the rotation speed of each wheel to VCIB 111 as one of pieces of information included in a vehicle status.

Brake system 121 generates a braking command to a braking apparatus in accordance with a prescribed control request outputted from ADK 200 through VCIB 111 and integrated control manager 115 and controls the braking apparatus based on the generated braking command.

Steering system 122 is configured to control a steering angle of a steering wheel of vehicle 10 with a steering apparatus. The steering apparatus includes, for example, rack-and-pinion electric power steering (EPS) that allows adjustment of a steering angle by an actuator.

A pinion angle sensor 128 is connected to steering system 122. Pinion angle sensor 128 detects an angle of rotation of a pinion gear (a pinion angle) coupled to a rotation shaft of the actuator included in the steering apparatus. Pinion angle sensor 128 provides a detected pinion angle to steering system 122. Steering system 122 provides the pinion angle as one of pieces of information included in the vehicle status to VCIB 111.

Steering system 122 generates a steering command to the steering apparatus in accordance with a prescribed control request outputted from ADK 200 through VCIB 111 and integrated control manager 115. Steering system 122 controls the steering apparatus based on the generated steering command.

Powertrain system 123 controls an electric parking brake (EPB) provided in at least one of a plurality of wheels provided in vehicle 10, a P-Lock apparatus provided in a transmission of vehicle 10, a shift apparatus configured to select any shift range from among a plurality of shift ranges, and a drive source of vehicle 10. Detailed description will be given later.

Active safety system 125 detects an obstacle (an obstacle or a human) in front or in the rear with the use of a camera 129A and radar sensors 129B and 129C. When active safety system 125 determines that there is possibility of collision based on a distance to the obstacle or the like and a direction of movement of vehicle 10, it outputs a braking command to brake system 121 through integrated control manager 115 so as to increase braking force.

Body system 126 is configured to control, for example, components such as a direction indicator, a horn, or a wiper, depending on a status of travel or an environment around vehicle 10. Body system 126 controls the above-described component in accordance with a prescribed control request outputted from ADK 200 through VCIB 111 and integrated control manager 115.

Vehicle 10 may be adopted as one of constituent elements of a mobility as a service (MaaS) system. The MaaS system further includes, for example, a data server, a mobility service platform (which is denoted as “MSPF” below), and autonomous driving related mobility services (none of which is shown), in addition to vehicle 10.

Vehicle 10 further includes a data communication module (DCM) (not shown) as a communication interface (I/F) to wirelessly communicate with the data server described above. The DCM outputs various types of vehicle information such as a speed, a position, or an autonomous driving state to the data server. The DCM receives from the autonomous driving related mobility services through the MSPF and the data server, various types of data for management of travel of an autonomous driving vehicle including vehicle 10 in the mobility services.

The MSPF is an integrated platform to which various mobility services are connected. In addition to autonomous driving related mobility services, not-shown various mobility services (for example, various mobility services provided by a ride-share company, a car-sharing company, an insurance company, a rent-a-car company, and a taxi company) are connected to the MSPF. Various mobility services including mobility services can use various functions provided by the MSPF by using APIs published on the MSPF, depending on service contents.

The autonomous driving related mobility services provide mobility services using an autonomous driving vehicle including vehicle 10. The mobility services can obtain operation control data of vehicle 10 that communicates with the data server or information stored in the data server from the MSPF by using the APIs published on the MSPF. The mobility services transmit data for managing an autonomous driving vehicle including vehicle 10 to the MSPF by using the API.

The MSPF publishes APIs for using various types of data on vehicle statuses and vehicle control necessary for development of the ADS. An ADS provider can use as the APIs, the data on the vehicle statuses and vehicle control necessary for development of the ADS stored in the data server.

FIG. 2 is a diagram for illustrating in detail, a configuration of ADS 202, VCIB 111, and VP 120. As shown in FIG. 2 , ADS 202 includes a compute assembly 210, a human machine interface (HMI) 230, sensors for perception 260, sensors for pose 270, and a sensor cleaning 290.

During autonomous driving of the vehicle, compute assembly 210 obtains information indicating an environment around the vehicle and information indicating a pose, a behavior, and a position of the vehicle from various sensors which will be described later, and obtains a vehicle status from VP 120 which will be described later through VCIB 111 and sets a next operation (acceleration, deceleration, or turning) of vehicle 10. Compute assembly 210 outputs various commands for realizing a set next operation of the vehicle to VCIB 111. Compute assembly 210 includes communication modules 210A and 210B. Communication modules 210A and 210B are configured to communicate with VCIB 111.

HMI 230 presents information to a user and accepts an operation by the user during autonomous driving, during driving requiring an operation by the user, or at the time of transition between autonomous driving and driving requiring an operation by the user. HMI 230 is constructed to be connected to an input and output apparatus such as a touch panel display, a display apparatus, and an operation apparatus provided in base vehicle 100.

Sensors for perception 260 include sensors that perceive an environment around vehicle 10 and include, for example, at least one of laser imaging detection and ranging (LIDAR), a millimeter-wave radar, and a camera.

The LIDAR refers to a distance measurement apparatus that measures a distance based on a time period from emission of pulsed laser beams (infrared rays) until return of the laser beams reflected by an object. The millimeter-wave radar is a distance measurement apparatus that measures a distance or a direction to an object by emitting radio waves short in wavelength to the object and detecting radio waves that return from the object. The camera is arranged, for example, on a rear side of a room mirror in a compartment and used for shooting an image of the front of the vehicle. Information obtained by sensors for perception 260 is outputted to compute assembly 210. As a result of image processing by artificial intelligence (AI) or an image processing processor onto images or video images shot by the camera, another vehicle, an obstacle, or a human in front of the vehicle can be recognized.

Sensors for pose 270 include sensors that detect a pose, a behavior, or a position of the vehicle, and include, for example, an inertial measurement unit (IMU) or a global positioning system (GPS).

The IMU detects, for example, an acceleration in a front-rear direction, a lateral direction, and a vertical direction of the vehicle and an angular speed in a roll direction, a pitch direction, and a yaw direction of the vehicle. The GPS detects a position of vehicle 10 based on information received from a plurality of GPS satellites that orbit the Earth. Information obtained by sensors for pose 270 is outputted to compute assembly 210.

Sensor cleaning 290 is configured to remove soiling attached to various sensors during traveling of the vehicle. Sensor cleaning 290 removes soiling attached to a lens of the camera or a portion from which laser beams or radio waves are emitted, for example, with a cleaning solution or a wiper.

VCIB 111 includes a VCIB 111A and a VCIB 111B. Each of VCIBs 111A and 111B contains a central processing unit (CPU) and a memory (for example, a read only memory (ROM) and a random access memory (RAM)), neither of which is shown. Though VCIB 111A is equivalent in function to VCIB 111B, it is partially different in a plurality of systems connected to the VCIBs that make up VP 120.

VCIBs 111A and 111B are communicatively connected to communication modules 210A and 210B of compute assembly 210, respectively. VCIB 111A and VCIB 111B are communicatively connected to each other.

VCIBs 111A and 111B each relay various commands corresponding to control requests from ADS 202 and output them as control commands to a corresponding system of VP 120. More specifically, each of VCIB 111A and VCIB 111B uses various commands provided from ADS 202 based on information (for example, an API) such as a program stored in the memory to generate a control command to be used for control of a corresponding system of VP 120 and outputs the control command to the corresponding system. VCIBs 111A and 111B each relay vehicle information provided from each system of VP 120 and provide the vehicle information as a vehicle status to ADS 202. The information indicating the vehicle status may be information identical to the vehicle information or may be information extracted from the vehicle information to be used for processing performed by ADS 202.

As VCIBs 111A and 111B equivalent in function relating to an operation of at least one of (for example, braking or steering) systems are provided, control systems between ADS 202 and VP 120 are redundant. Thus, when some kind of failure occurs in a part of the system, the function (turning or stopping) of VP 120 can be maintained by switching between the control systems as appropriate or disconnection of a control system where failure has occurred.

Brake system 121 includes brake systems 121A and 121B. Steering system 122 includes steering systems 122A and 122B. Powertrain system 123 includes an EPB system 123A, a P-Lock system 123B, and a propulsion system 124.

VCIB 111A is communicatively connected to brake system 121A, steering system 122A, EPB system 123A, P-Lock system 123B, propulsion system 124, and body system 126 of the plurality of systems of VP 120 through a communication bus.

VCIB 111B is communicatively connected to brake system 121B, steering system 122B, and P-Lock system 123B of the plurality of systems of VP 120 through a communication bus.

Brake systems 121A and 121B are configured to control a plurality of braking apparatuses provided in wheels of the vehicle. Brake system 121A may be equivalent in function to brake system 121B, or one of them may be configured to independently control braking force of each wheel during travel of the vehicle and the other thereof may be configured to control braking force such that equal braking force is generated in the wheels during travel of the vehicle.

Brake systems 121A and 121B generate braking commands to the braking apparatuses in accordance with a control request outputted from ADS 202 through VCIB 111A and VCIB 111B, respectively. For example, brake systems 121A and 121B control the braking apparatuses based on a braking command generated in one of the brake systems, and when a failure occurs in that brake system, the braking apparatuses are controlled based on a braking command generated in the other brake system.

Steering systems 122A and 122B are configured to control a steering angle of a steering wheel of vehicle 10 with a steering apparatus. Steering system 122A is similar in function to steering system 122B.

Steering systems 122A and 122B generate steering commands to the steering apparatus in accordance with a control request outputted from ADS 202 through VCIB 111A and VCIB 111B, respectively. For example, steering systems 122A and 122B control the steering apparatus based on the steering command generated in one of the steering systems, and when a failure occurs in that steering system, the steering apparatus is controlled based on a steering command generated in the other steering system.

EPB system 123A is configured to control the EPB. The EPB fixes a wheel by an operation of an actuator. The EPB, for example, activates with an actuator, a drum brake for a parking brake provided in at least one of a plurality of wheels provided in vehicle 10 to fix the wheel, or activates a braking apparatus to fix a wheel with an actuator capable of regulating a hydraulic pressure to be supplied to the braking apparatus separately from brake systems 121A and 121B.

EPB system 123A controls the EPB in accordance with a control request outputted from ADS 202 through VCIB 111A.

P-Lock system 123B is configured to control a P-Lock apparatus. The P-Lock apparatus fits a protrusion provided at a tip end of a parking lock pawl, a position of which is adjusted by an actuator, into a tooth of a gear (locking gear) provided as being coupled to a rotational element in the transmission of vehicle 10. Rotation of an output shaft of the transmission is thus fixed so that fixing of rotation of the wheel (which is also referred to as “fixing of wheels” below) of a drive wheel is carried out.

P-Lock system 123B controls the P-Lock apparatus in accordance with a control request provided from ADS 202 through VCIB 111A. For example, when the control request provided from ADS 202 through VCIB 111A includes a control request to set the shift range to a parking range (which is denoted as a P range below), P-Lock system 123B activates the P-Lock apparatus, and when the control request includes a control request to set the shift range to a shift range other than the P range, it deactivates the P-Lock apparatus.

Propulsion system 124 is configured to switch a shift range with the use of a shift apparatus and to control driving force of vehicle 10 in a direction of movement of vehicle 10 that is generated from a drive source. Switchable shift ranges include, for example, the P range, a neutral range (which is denoted as an N range below), a forward travel range (which is denoted as a D range below), and a rearward travel range (which is denoted as an R range below). The drive source includes, for example, a motor generator and an engine.

Propulsion system 124 controls the shift apparatus and the drive source in accordance with a control request provided from ADS 202 through VCIB 111A. For example, when a control request provided from ADS 202 through VCIB 111A includes a control request to set the shift range to the P range, propulsion system 124 controls the shift apparatus to set the shift range to the P range.

Active safety system 125 is communicatively connected to brake system 121A. As described above, active safety system 125 detects an obstacle (an obstacle or a human) in front by using camera 129A and radar sensor 129B, and when it determines that there is possibility of collision based on a distance to the obstacle, it outputs a braking command to brake system 121A so as to increase braking force.

Body system 126 controls components such as a direction indicator, a horn, or a wiper in accordance with a control request provided from ADS 202 through VCIB 111A.

An operation apparatus manually operable by a user for the braking apparatus, the steering apparatus, the EPB, the P-Lock apparatus, the shift apparatus, and the drive source described above may separately be provided.

Various commands corresponding to control requests provided from ADS 202 to VCIB 111 include a propulsion direction command requesting switching of the shift range, an immobilization command requesting activation or deactivation of the EPB and the P-Lock apparatus, an acceleration command requesting acceleration or deceleration of vehicle 10, a wheel steer angle command requesting a wheel steer angle of a steering wheel, an autonomization command requesting switching of an autonomous state between an autonomous mode and a manual mode, and a standstill command requesting keeping on stationary or keeping off stationary of the vehicle.

For example, when an autonomous mode is selected as the autonomous state by an operation by the user onto HMI 230 in vehicle 10 configured as above, autonomous driving is carried out. During autonomous driving, ADS 202 initially creates a driving plan as described above. Examples of the driving plan include a plurality of plans relating to operations of vehicle 10 such as a plan to continue straight travel, a plan to turn left or right at a prescribed intersection on a predetermined travel path, and a plan to change a travel lane to a lane different from the lane where the vehicle currently travels.

ADS 202 extracts a controllable physical quantity (for example, an acceleration or a deceleration, and a wheel steer angle) necessary for operations of vehicle 10 in accordance with the created driving plan. ADS 202 splits the physical quantity for each execution cycle time of the API. ADS 202 executes the API with the use of the resultant physical quantity and outputs various commands to VCIB 111. Furthermore, ADS 202 obtains a vehicle status (for example, an actual direction of movement of vehicle 10 and a state of fixation of the vehicle) from VP 120 and creates again the driving plan on which the obtained vehicle status is reflected. ADS 202 thus allows autonomous driving of vehicle 10.

In control of a wheel steer angle (steering angle) in accordance with a request during autonomous driving of vehicle 10, when the steering angle abruptly changes with sudden increase in requested amount of the wheel steer angle, stability of vehicle 10 may become poor.

In the present embodiment, in steering in accordance with a wheel steer angle command set based on a wheel steer angle of the front wheel which is the steering wheel, it is assumed that the wheel steer angle requested in the wheel steer angle command is set not to exceed a restriction range of a rate of the wheel steer angle that is set based on the velocity of vehicle 10 (which is also denoted as the vehicle velocity).

The wheel steer angle command is thus set not to exceed the restriction range of the rate of the steer angle. Therefore, even when the requested amount of the wheel steer angle of the steering wheel suddenly increases, abrupt change in steering angle is suppressed. Therefore, degradation of stability of vehicle 10 can be suppressed.

Processing performed by ADS 202 (more specifically, compute assembly 210) in the present embodiment will be described below with reference to FIG. 3 . FIG. 3 is a flowchart showing exemplary processing for setting a reference value performed in ADS 202. ADS 202 repeatedly performs processing as below, for example, each time a predetermined period elapses.

In step (the step being denoted as S below) 11, ADS 202 determines whether or not vehicle 10 is traveling straight. For example, when a while line indicating a travel lane over which vehicle 10 travels is a straight line having a prescribed length or longer, ADS 202 may determine that vehicle 10 is traveling straight, or when records of movement of vehicle 10 based on the GPS indicate a straight line having a prescribed length or longer, ADS 202 may determine that vehicle 10 is traveling straight. When vehicle 10 is determined as traveling straight (YES in S11), the process proceeds to S12.

In S12, ADS 202 obtains the wheel steer angle of the front wheel which is the steering wheel. ADS 202 obtains the wheel steer angle of the front wheel based on a vehicle status provided from base vehicle 100 through vehicle control interface box 111. Base vehicle 100 (specifically, steering system 122) obtains a pinion angle based on a result of detection by pinion angle sensor 128 and calculates the wheel steer angle of the front wheel based on the obtained pinion angle. Base vehicle 100 calculates the wheel steer angle of the front wheel each time a predetermined period elapses, and provides the calculated wheel steer angle of the front wheel as one of pieces of information included in the vehicle status to ADS 202 through vehicle control interface box 111.

In S13, ADS 202 sets a reference value. ADS 202 sets a value expressing the obtained wheel steer angle of the front wheel as the reference value. When vehicle 10 is determined as not traveling straight (NO in S11), this process ends.

For example, when switching to the autonomous mode is made after the reference value is set, ADS 202 sets an initial value of the wheel steer angle command corresponding to the steering angle set in accordance with the driving plan, based on the reference value.

Processing performed in ADS 202 in the autonomous mode will be described with reference to FIG. 4 . FIG. 4 is a flowchart showing exemplary processing performed in ADS 202 in the autonomous mode.

In S21, ADS 202 determines whether or not an autonomous state has been set to an autonomous mode. ADS 202 determines whether or not the autonomous state has been set to the autonomous mode, for example, based on a status of a flag indicating the autonomous mode. The flag indicating the autonomous mode is turned on, for example, when an operation to carry out autonomous driving onto HMI 230 by the user is accepted and turned off when the autonomous mode is canceled and switching to the manual mode is made in response to an operation by the user or in accordance with a condition of drive. When the autonomous state is determined as having been set to the autonomous mode (YES in S21), the process proceeds to S22.

In S22, ADS 202 sets the initial value of the wheel steer angle command. ADS 202 sets the initial value of the wheel steer angle command in accordance with the driving plan. For example, when the driving plan is a driving plan to travel straight, ADS 202 sets a relative value between a current value of the wheel steer angle and the reference value as the initial value of the wheel steer angle command. For example, when the driving plan is a driving plan to turn left at a predetermined steering angle, ADS 202 sets a relative value between the current value of the wheel steer angle and a value calculated by adding a value corresponding to the predetermined steering angle to the reference value as the initial value of the wheel steer angle command. For example, when the driving plan is a driving plan to turn right at a predetermined steering angle, ADS 202 sets a relative value between the current value of the wheel steer angle and a value calculated by subtracting a value corresponding to the predetermined steering angle from the reference value as the initial value of the wheel steer angle command.

In S23, ADS 202 obtains a wheel steer angle rate limitation of the front wheel which is the steering wheel. ADS 202 sets the wheel steer angle rate limitation based on relation between a vehicle velocity and a wheel steer angle rate limitation as shown in FIGS. 5 and 6 . FIG. 5 is a diagram showing in a table format, relation between a vehicle velocity and a wheel steer angle rate limitation. FIG. 6 is a map showing relation between a vehicle velocity and a wheel steer angle rate limitation.

FIG. 5 shows wheel steer angle rate limitations when the vehicle velocity is set to zero, 36 km/h, 40 km/h, 67 km/h, and 84 km/h. FIG. 6 shows wheel steer angle rate limitations set in accordance with the vehicle velocity within a range of the vehicle velocity from zero to 80 km/h.

For example, FIGS. 5 and 6 show that 0.751 [rad/sec.] is set as the wheel steer angle rate limitation, for example, when the vehicle velocity is within the range from zero to 36 km/h. FIGS. 5 and 6 show that 0.469 [rad/sec.] is set as the wheel steer angle rate limitation, for example, when the vehicle velocity is set to 40 km/h. FIGS. 5 and 6 show that the wheel steer angle rate limitation is set to linearly vary with variation in vehicle velocity (for example, when the vehicle velocity increases, the limitation is lowered by an amount in proportion to an amount of increase) between 0.751 [rad/sec.] and 0.469 [rad/sec.] when the vehicle velocity varies between 36 km/h and 40 km/h. FIGS. 5 and 6 show that 0.287 [rad/sec.] is set as the wheel steer angle rate limitation, for example, when the vehicle velocity is set to 67 km/h. FIGS. 5 and 6 show that the wheel steer angle rate limitation is set to linearly vary with variation in vehicle velocity between 0.469 [rad/sec.] and 0.287 [rad/sec.] when the vehicle velocity varies between 40 km/h and 67 km/h. FIGS. 5 and 6 show that 0.253 [rad/sec.] is set as the wheel steer angle rate limitation when the vehicle velocity is set to 84 km/h. In FIGS. 5 and 6 , the wheel steer angle rate limitation is set to linearly vary with variation in vehicle velocity between 0.287 [rad/sec.] and 0.253 [rad/sec.] when the vehicle velocity varies between 67 km/h and 84 km/h. The limitation of the rate corresponding to the vehicle velocity shown in FIGS. 5 and 6 is a predetermined value adapted through experiments or the like.

ADS 202 obtains information on the vehicle velocity of vehicle 10 as a vehicle status from VP 120. For example, information on a velocity of vehicle 10 (a velocity in the direction of travel of vehicle 10) calculated based on a wheel speed obtained by wheel speed sensor 127A or wheel speed sensor 127B is outputted as the vehicle status from base vehicle 100 through VCIB 111 to ADS 202. ADS 202 obtains the wheel steer angle rate limitation based on the obtained vehicle velocity and the above-described relation between the vehicle velocity and the wheel steer angle rate limitation shown in FIGS. 5 and 6 .

In S24, ADS 202 determines whether or not magnitude of the initial value of the wheel steer angle command is larger than the wheel steer angle limitation. ADS 202 obtains, for example, an absolute value of the initial value of the wheel steer angle command as magnitude of the initial value of the wheel steer angle command. ADS 202 calculates the wheel steer angle limitation from the wheel steer angle rate limitation. ADS 202 calculates the wheel steer angle limitation, for example, by multiplying the wheel steer angle rate limitation by a value corresponding to a control cycle (computation cycle). When the magnitude of the initial value of the wheel steer angle command is determined as being larger than the wheel steer angle limitation (YES in S24), the process proceeds to S25.

In S25, ADS 202 sets the wheel steer angle command based on the wheel steer angle limitation. In other words, ADS 202 changes only the magnitude of the initial value to the wheel steer angle limitation, with the sign of the wheel steer angle command being maintained, and sets the resultant value as the wheel steer angle command. When the magnitude of the initial value of the wheel steer angle command is determined as being equal to or smaller than the wheel steer angle limitation (NO in S24), the process proceeds to S26.

In S26, ADS 202 transmits the set wheel steer angle command to VCIB 111.

Processing performed in VCIB 111 (more specifically, VCIB 111A or VCIB 111B) will now be described with reference to FIG. 7 . FIG. 7 is a flowchart showing exemplary processing performed in VCIB 111.

In S31, VCIB 111 determines whether or not it has received the wheel steer angle command from ADS 202. When the VCIB is determined as having received the wheel steer angle command (YES in S31), the process proceeds to S32.

In S32, VCIB 111 controls the steering apparatus. VCIB 111 controls the steering apparatus in accordance with the received wheel steer angle command. In other words, VCIB 111 controls the steering apparatus to steer the vehicle by the relative value of the steering angle indicated in the wheel steer angle command.

In S33, VCIB 111 obtains the front wheel steer angle. In S34, VCIB 111 transmits the obtained wheel steer angle as one of pieces of information of the vehicle statuses to ADS 202.

An operation of ADS 202 based on the structure and the flowchart as above will be described.

For example, when vehicle 10 travels straight (YES in S11), the front wheel steer angle is obtained from base vehicle 100 (S12) and the value indicating the obtained front wheel steer angle is set as the reference value (S13).

For example, when the autonomous mode has been set as the autonomous state (YES in S21), the initial value of the wheel steer angle command is set in accordance with the driving plan (S22). At this time, a relative value from the current value of the wheel steer angle to a value corresponding to the steering angle in accordance with the driving plan is set as the initial value of the wheel steer angle command.

Thereafter, the wheel steer angle rate limitation is obtained based on the vehicle velocity (S23). Specifically, the vehicle velocity is obtained from base vehicle 100, and the wheel steer angle rate limitation is obtained based on the obtained vehicle velocity and the relation between the vehicle velocity and the limitation shown in FIGS. 5 and 6 . When magnitude of the set initial value is larger than the wheel steer angle limitation calculated based on the wheel steer angle rate limitation (YES in S24), the wheel steer angle limitation is set as the wheel steer angle command (S25) and the set wheel steer angle command is transmitted to VCIB 111 (S26). When magnitude of the set initial value is equal to or smaller than the wheel steer angle limitation (NO in S24), the initial value of the wheel steer angle is transmitted as the wheel steer angle command to VCIB 111 (S26).

When VCIB 111 receives the wheel steer angle command (YES in S31), the steering apparatus of base vehicle 100 is controlled (S32). Thereafter, the wheel steer angle is obtained (S33) and the wheel steer angle is transmitted to ADS 202 (S34).

As set forth above, according to vehicle 10 in the present embodiment, the wheel steer angle command is set not to exceed the restriction range of the rate of the steer angle. Therefore, even when the requested amount of the wheel steer angle of the front wheel which is the steering wheel suddenly increases, abrupt change in steering angle is suppressed. Therefore, degradation of stability of vehicle 10 can be suppressed. Therefore, a vehicle on which an autonomous driving system is mountable, a method of controlling a vehicle, and a vehicle control interface box that achieve improvement in stability of steering during autonomous driving can be provided.

Since magnitude of the upper limit value of the wheel steer angle rate is smaller as the vehicle velocity is higher, abrupt change in steering angle is suppressed. Therefore, degradation of stability of the vehicle can be suppressed.

A modification will be described below.

Though VCIB 111A or VCIB 111B is described as performing the processing shown in the flowchart in FIG. 5 in the embodiment above, for example, VCIB 111A and VCIB 111B may perform the processing described above in coordination.

Though vehicle control interface box 111 is described as performing the processing shown in the flowchart in FIG. 5 in the embodiment above, for example, a part or the entirety of the processing described above may be performed by a system (specifically, steering system 122A or steering system 122B) to be controlled by VP 120.

The entirety or a part of the modification may be carried out as being combined as appropriate.

Example

API Specification for TOYOTA Vehicle Platform

Ver. 1.1

Records of Revision

Date of Revision ver. Overview of Revision Reviser 2020 1.0 Creating a new material TOYOTA May 23 MOTOR Corp. 2021 1.1 The figure of Front Wheel Steer TOYOTA Apr. 14 Angle Rate Limitation is updated. MOTOR Corp. Explanation of Standstill Status is added.

TABLE of Contents 1. Introduction   1.1. Purpose of this Specification   1.2. Target Vehicle   1.3. Definition of Term 2. Structure   2.1. Overall Structure of Autono-MaaS Vehicle   2.2. System Structure of Autono-MaaS Vehicle 3. Application Interfaces   3.1. Typical Usage of APIs   3.2. APIs for Vehicle Motion Control     3.2.1. API List for Vehicle Motion Control     3.2.2. Details of Each API for Vehicle Motion Control   3.3. APIs for BODY Control     3.3.1. API List for BODY Control     3.3.2. Details of Each API for BODY Control   3.4. APIs for Power Control     3.4.1. API List for Power Control     3.4.2. Details of Each API for Power Control   3.5. APIs for Failure Notification     3.5.1. API List for Failure Notification     3.5.2. Details of Each API for Failure Notification   3.6. APIs for Security     3.6.1. API List for Security     3.6.2. Details of Each API for Security 4. API Guides to Control Toyota Vehicles   4.1. APIs for Vehicle Motion Control     4.1.1. API List for Vehicle Motion Control     4.1.2. API Guides in Details for Vehicle Motion Control   4.2. APIs for BODY Control     4.2.1. API List for BODY Control   4.3. APIs for Power Control     4.3.1. API List for Power Control   4.4. APIs for Failure Notification     4.4.1. API List for Failure Notification   4.5. APIs for Security     4.5.1. API List for Security     4.5.2. API Guides in Details for Security

1. Introduction

1.1. Purpose of this Specification

This document is an API specification of vehicle control interface for Autono-MaaS vehicles and contains outline, the way to use and note of APIs.

1.2. Target Vehicle

This specification is applied to the Autono-MaaS vehicles defined by [Architecture Specification for TOYOTA Vehicle Platform attached with Automated Driving System].

1.3. Definition of Term

TABLE 1 Definition of Term Term Definition ADS Autonomous Driving System ADK Autonomous Driving Kit VP Vehicle Platform VCIB Vehicle Control Interface Box. This is an ECU for the interface and the signal converter between ADS and VP’s sub systems. PCS Pre-Collision Safety

2. Structure

2.1. Overall Structure of Autono-MaaS Vehicle

The overall structure of Autono-MaaS is shown (FIG. 8 ).

2.2. System Structure of Autono-MaaS Vehicle

System Architecture is shown in FIG. 9 .

3. Application Interfaces

3.1. Typical Usage of APIs

In this section, Typical Usage of APIs is described.

A typical workflow of APIs is as follows (FIG. 10 ). The following example assumes CAN for physical communication.

3.2. APIs for vehicle motion control

In this section, the APIs for vehicle motion control are described.

3.2.1. API List for Vehicle Motion Control

3.2.1.1. Inputs

TABLE 3 Input APIs for vehicle motion control Redun- Signal Name Description dancy Propulsion Direction Request for shift change from/to forward N/A Command (D range) to/from back (R range) Immobilization Request for turning on/off WheelLock Applied Command Standstill Command Request for keeping on/off stationary Applied Acceleration Command Request for acceleration/deceleration Applied Front Wheel Steer Request for front wheel steer angle Applied Angle Command Vehicle Mode Request for changing from/to manual Applied Command mode to/from Autonomous Mode High Dynamics Request for increasing braking response Applied Command performance* *Reaction time in VP upon a request from ADK

3.2.1.2. Outputs

TABLE 4 Output APIs for vehicle motion control Redun- Signal Name Description dancy Propulsion Direction Current shift status N/A Status Immobilization Status Status of immobilization (i.e. EPB and Shift P) Applied Standstill Status Standstill status N/A Estimated Gliding Acceleration Estimated vehicle acceleration/ deceleration when throttle is N/A fully closed Estimated maximum acceleration Estimated maximum acceleration Applied Estimated maximum deceleration Estimated maximum deceleration Applied Front wheel steer angle Front wheel steer angle Applied Front wheel steer angle rate Front wheel steer angle rate Applied Front wheel steer angle rate limitation Road wheel angle rate limit Applied Estimated maximum Estimated max lateral acceleration Applied lateral acceleration Estimated maximum Estimated max lateral Applied lateral acceleration rate acceleration rate Intervention of accelerator pedal This signal shows whether t he accelerator pedal is N/A depressed by a driver (intervention) Intervention of brake pedal This signal shows whether the brake pedal is depressed by a N/A driver (intervention) Intervention of steering wheel This signal shows whether the steering wheel is turned by a N/A driver (intervention) Intervention of shift lever This signal shows whether the shift lever is controlled by a N/A driver (intervention) Wheel speed pulse (front left) Pulse from wheel speed sensor (Front Left Wheel) N/A Wheel rotation direction (front left) Rotation direction of wheel (Front Left) N/A Wheel speed pulse (front right) Pulse from wheel speed sensor (Front Right Wheel) N/A Wheel rotation direction (front right) Rotation direction of wheel (Front Right) N/A Wheel speed pulse (rear left) Pulse from wheel speed sensor (Rear Left Wheel) Applied Wheel rotation direction (Rear left) Rotation direction of wheel (Rear Left) Applied Wheel speed pulse (rear right) Pulse from wheel speed sensor (Rear Right Wheel) Applied Wheel rotation direction (Rear right) Rotation direction of wheel (Rear Right) Applied Traveling direction Moving direction of vehicle Applied Vehicle velocity Estimated longitudinal velocity of vehicle Applied Longitudinal acceleration Estimated longitudinal acceleration of vehicle Applied Lateral acceleration Sensor value of lateral acceleration of vehicle Applied Yawrate Sensor value of yaw rate Applied Slipping Detection Detection of tire glide/spin/skid Applied Vehicle mode state State of whether Autonomous Mode, manual mode Applied Readiness for autonomization Situation of whether the vehicle can transition to Autonomous Applied Mode or not Failure status of VP functions for This signal is used to show whether VP functions have some Applied Autonomous Mode failures mode when a vehicle works as Autonomous Mode. PCS Alert Status Status of PCS (Alert) N/A PCS Preparation Status Status of PCS (Prefill) N/A PCS Brake/PCS Brake Hold Status Status of PCS (PB/PBH) N/A ADS/PCS arbitration status ADS/PCS arbitration status N/A

3.2.2. Details of Each API for Vehicle Motion Control

3.2.2.1. Propulsion Direction Command

Request for shift change from/to forward (D range) to/from back (R range)

Values

Value Description Remarks 0 No Request 2 R Shift to R range 4 D Shift to D range other Reserved

Remarks

-   -   Available only when Vehicle mode state=“Autonomous Mode.”     -   Available only when a vehicle is stationary (Traveling         direction=“standstill”).     -   Available only when brake is applied.

3.2.2.2. Immobilization Command

Request for turning on/off WheelLock

Values

The following table shows a case where EPB and Shift P are used for immobilization.

Value Description Remarks 0 No Request 1 Applied EPB is turned on and shift position is changed to “P” 2 Released EPB is turned off and shift position is changed to the value of Propulsion Direction Command

Remarks

-   -   This API is used for parking a vehicle.     -   Available only when Vehicle mode state=“Autonomous Mode.”     -   Changeable only when the vehicle is stationary (Traveling         direction=“standstill”).     -   Changeable only while brake is applied.

3.2.2.3. Standstill Command

Request for applying/releasing brake holding function

Values

Value Description Remarks 0 No Request 1 Applied Brake holding function is allowed. 2 Released

Remarks

-   -   This API is used for choosing a status of whether the brake         holding function is allowed.     -   Available only when Vehicle mode state=“Autonomous Mode.”     -   Acceleration Command (deceleration request) has to be continued         until Standstill Status becomes “Applied”.

3.2.2.4. Acceleration Command

Request for acceleration

Values

Estimated maximum deceleration to Estimated maximum acceleration [m/s²]

Remarks

-   -   Available only when Vehicle mode state=“Autonomous Mode.”     -   Acceleration (+) and deceleration (—) request based on         Propulsion Direction Status direction.     -   The upper/lower limit will vary based on Estimated maximum         deceleration and Estimated maximum acceleration.     -   When acceleration more than Estimated maximum acceleration is         requested, the request is set to Estimated maximum acceleration.     -   When deceleration more than Estimated maximum deceleration is         requested, the request is set to Estimated maximum deceleration.     -   In case where a driver operates a vehicle (over-ride), the         requested acceleration may not be achieved.     -   When PCS simultaneously works, VP should choose minimum         acceleration (maximum deceleration).

3.2.2.5. Front Wheel Steer Angle Command

Values

Value Description Remarks — [unit: rad]

Remarks

-   -   Available only when Vehicle mode state=“Autonomous Mode”     -   Left is positive value (+). Right is negative value (−).     -   Front wheel steer angle is set to value (0) when the vehicle is         going straight.     -   This request is set as a relative value from the current one to         prevent misalignment of “Front Wheel Steer Angle” from being         accumulated.     -   The request value should be set within Front wheel steer angle         rate limitation.     -   In case where a driver operates a vehicle (over-ride), the         requested Front Wheel Steer Angle may not be achieved.

3.2.2.6. Vehicle Mode Command

Request for changing from/to manual mode to/from Autonomous Mode

Values

Value Description Remarks 0 No Request 1 Request For Autonomy 2 Deactivation Request means transition request to manual mode

Remarks

N/A

3.2.2.7. High Dynamics Command

If ADK would like to increase braking response performance* of VP, High Dynamics Command should be set to “High”.

*Reaction time in VP upon a request from ADK

Values

Value Description Remarks 0 No Request 1 High 2-3 Reserved

Remarks

N/A

3.2.2.8. Propulsion Direction Status

Current shift Status

Value Description Remarks 0 Reserved 1 P 2 R 3 N 4 D 5 Reserved 6 Invalid value

Remarks

-   -   If VP does not know the current shift status, this output is set         to “Invalid Value.”

3.2.2.9. Immobilization Status

Each immobilization system status

Values

The following table shows a case where EPB and Shift P are used for immobilization.

Value Shift EPB Description Remarks 0 0 Shift set to other than P, and EPB Released 1 0 Shift set to P and EPB Released 0 1 Shift set to other than P, and EPB applied 1 1 Shift set to P and EPB Applied

Remarks

-   -   N/A

3.2.2.10. Standstill Status

Status of Standstill

Value Description Remarks 0 Released 1 Applied 2 Reserved 3 Invalid value

Remarks

-   -   N/A

3.2.2.11. Estimated Gliding Acceleration

Acceleration calculated in VP in case that throttle is closed, considering slope, road load and etc.

Values

[unit: m/s²]

Remarks

-   -   When the Propulsion Direction Status is “D”, acceleration for         forward direction shows a positive value.     -   When the Propulsion Direction Status is “R”, acceleration for         reverse direction shows a positive value.

3.2.2.12. Estimated Maximum Acceleration

Acceleration calculated in VP in case that throttle is fully open, considering slope, road load and etc.

Values

[unit: m/s²]

Remarks

-   -   When the Propulsion Direction Status is “D”, acceleration for         forward direction shows a positive value.     -   When the Propulsion Direction Status is “R”, acceleration for         reverse direction shows a positive value.

3.2.2.13. Estimated Maximum Deceleration

Maximum deceleration calculated in VP in case that brake in VP is requested as maximum, considering slope, road load and etc.

Values

[unit: m/s²]

Remarks

-   -   When the Propulsion Direction Status is “D”, deceleration for         forward direction shows a negative value.     -   When the Propulsion Direction Status is “R”, deceleration for         reverse direction shows a negative value.

3.2.2.14. Front wheel steer angle

Values

Value Description Remarks Minimum Value Invalid value others [unit: rad]

Remarks

-   -   Left is positive value (+). Right is negative value (−).     -   This signal should show invalid value until VP can calculate         correct value or when the sensor is invalid/failed.

3.2.2.15. Front wheel steer angle rate

Front wheel steer angle rate

Values

Value Description Remarks Minimum Value Invalid value others [unit: rad/s]

Remarks

-   -   Left is positive value (+). Right is negative value (−).     -   This signal should show invalid value until VP can calculate         correct value or when Front wheel steer angle shows the minimum         value.

3.2.2.16. Front wheel steer angle rate limitation

The limit of the Front wheel steer angle rate

Values

[unit: rad/s]

Remarks

The limitation is calculated from the “vehicle speed—steering angle rate” map as shown in following Table 5 and FIG. 11 .

A) At a low speed or stopped situation, use fixed value (0.751 [rad/s]).

B) At a higher speed, the steering angle rate is calculated from the vehicle speed using 3.432 m/s³.

TABLE 5 “vehicle speed-steering angle rate” map Velocity [km/h] 0.0 36.0 40.0 67.0 84.0 Front Wheel Steer Angle Rate 0.751 0.751 0.469 0.287 0.253 Limitation [rad/s]

3.2.2.17. Estimated maximum lateral acceleration

Values

[unit: m/s²] (fixed value: 3.432)

Remarks

-   -   Maximum lateral acceleration defined for VP.

3.2.2.18. Estimated maximum lateral acceleration rate

Values

[unit: m/s³] (fixed value: 3.432)

Remarks

-   -   Maximum lateral acceleration rate defined for VP.

3.2.2.19. Intervention of accelerator pedal

This signal shows whether the accelerator pedal is depressed by a driver (intervention).

Values

Value Description Remarks 0 Not depressed 1 depressed 2 Beyond autonomy acceleration

Remarks

-   -   When a position of accelerator pedal is higher than a defined         threshold, this signal is set to “depressed”.     -   When the requested acceleration calculated from a position of         accelerator pedal is higher than the requested acceleration from         ADS, this signal is set as “Beyond autonomy acceleration.”

3.2.2.20. Intervention of brake pedal

This signal shows whether the brake pedal is depressed by a driver (intervention).

Values

Value Description Remarks 0 Not depressed 1 depressed 2 Beyond autonomy deceleration

Remarks

-   -   When a position of brake pedal is higher than the defined         threshold value, this signal is set to “depressed”.     -   When the requested deceleration calculated from a position of         brake pedal is higher than the requested deceleration from ADS,         this signal is set as “Beyond autonomy deceleration”.

3.2.2.21. Intervention of steering wheel

This signal shows whether the steering wheel is operated by a driver (intervention).

Values

Value Description Remarks 0 Not turned 1 ADS and driver collaboratively work 2 Only by human driver

Remarks

-   -   In “Intervention of steering wheel=1”, considering the human         driver's intent, EPS system drives the steering with the Human         driver collaboratively.     -   In “Intervention of steering wheel=2”, considering the human         driver's intent, the steering request from ADS is not achieved.         (The steering will be driven by human driver.)

3.2.2.22. Intervention of shift lever

This signal shows whether the shift lever is controlled by a driver (intervention)

Values

Value Description Remarks 0 OFF 1 ON Controlled (moved to any shift position)

Remarks

-   -   N/A

3.2.2.23. Wheel speed pulse (front left), Wheel speed pulse (front right), Wheel speed pulse (rear left), Wheel speed pulse (rear right)

Values

Value Description Remarks Maximum Value in Invalid value The sensor is invalid. transmission bits others ticks [unit: −] The number of pulses per one round wheel depends on VP.

Remarks

-   -   A pulse value is integrated at the pulse falling timing.     -   This wheel speed sensor outputs 96 pulses with a single         rotation.     -   Regardless of invalid/failure of wheel speed sensor, wheel speed         pulse will be updated.     -   When “1” is subtracted from a pulse value which shows “0”, the         value changes to “0×FF”. When “1” is added to a pulse value         which shows “0×FF”, the value changes to “0”.     -   Until the rotation direction is determined just after ECU is         activated, a pulse value will be added as the rotation direction         is “Forward”.     -   When detected forward rotation, a pulse value will be added.     -   When detected reverse rotation, a pulse value will be         subtracted.

3.2.2.24. Wheel rotation direction (front left), Wheel rotation direction (front right), Wheel rotation direction (Rear left), Wheel rotation direction (Rear right)

Values

Value Description Remarks 0 Forward 1 Reverse 2 Reserved 3 Invalid value The sensor is invalid.

Remarks

-   -   “Forward” is set until the rotation direction is determined         after VP is turned on.

3.2.2.25. Traveling direction

Moving direction of vehicle

Values

Value Description Remarks 0 Forward 1 Reverse 2 Standstill 3 Undefined

Remarks

-   -   This signal shows “Standstill” when four wheel speed values are         “0” during a constant time.     -   When shift is changed right after vehicle starts, it is possible         to be “Undefined”.

3.2.2.26. Vehicle velocity

Estimated longitudinal velocity of vehicle

Values

Value Description Remarks Maximum Value in Invalid value The sensor is invalid. transmission bits others Velocity [unit: m/s]

Remarks

-   -   The value of this signal is a positive value when both forward         direction and reverse direction.

3.2.2.27. Longitudinal acceleration

Estimated longitudinal acceleration of vehicle

Values

Value Description Remarks Minimum Value in Invalid value The sensor is transmission bits invalid. others Acceleration [unit: m/s²]

Remarks

-   -   Acceleration (+) and deceleration (—) value based on Propulsion         Direction Status direction.

3.2.2.28. Lateral acceleration

lateral acceleration of vehicle

Values

Value Description Remarks Minimum Value in Invalid value The sensor is transmission bits invalid. others Acceleration [unit: m/s²]

Remarks

-   -   A positive value shows counterclockwise. A negative value shows         clockwise.

3.2.2.29. Yaw rate

Sensor value of yaw rate

Values

Value Description Remarks Minimum Value in Invalid value The sensor is invalid. transmission bits others Yaw rate [unit: deg/s]

Remarks

-   -   A positive value shows counterclockwise. A negative value shows         clockwise.

3.2.2.30. Slipping Detection

Detection of tire glide/spin/skid

Value Description Remarks 0 Not Slipping 1 Slipping 2 Reserved 3 Invalid value

Remarks

-   -   This signal is determined as “Slipping” when any of the         following systems has been activated.         -   ABS (Anti-lock Braking System)         -   TRC (TRaction Control)         -   VSC (Vehicle Stability Control)         -   VDIM (Vehicle Dynamics Integrated Management)

3.2.2.31. Vehicle mode state

Autonomous or manual mode

Values

Value Description Remarks 0 Manual Mode The mode starts from Manual mode. 1 Autonomous Mode

Remarks

-   -   The initial state is set to “Manual Mode.”

3.2.2.32. Readiness for autonomization

This signal shows whether a vehicle can change to Autonomous Mode or not

Value Description Remarks 0 Not Ready For Autonomous Mode 1 Ready For Autonomous Mode 3 Invalid The status is not determined yet.

Remarks

-   -   N/A

3.2.2.33. Failure status of VP functions for Autonomous Mode

This signal is used to show whether VP functions have some failures mode when a vehicle works as Autonomous Mode.

Values

Value Description Remarks 0 No fault 1 Fault 3 Invalid The status is not determined yet.

Remarks

-   -   N/A

3.2.2.34. PCS Alert Status

Values

Value Description Remarks 0 Normal 1 Alert Request alert from PCS system 3 Unavailable

Remarks

N/A

3.2.2.35. PCS Preparation Status

Prefill Status as the preparation of PCS Brake

Values

Value Description Remarks 0 Normal 1 Active 3 Unavailable

Remarks

-   -   “Active” is a status in which PCS prepares brake actuator to         shorten the latency from a deceleration request issued by PCS.     -   When a value turns to “Active” during Vehicle mode         state=“Autonomous Mode,” “ADS/PCS arbitration status” shows         “ADS”.

3.2.2.36. PCS Brake/PCS Brake Hold Status

Values

Value Description Remarks 0 Normal 1 PCS Brake 2 PCS Brake Hold 7 Unavailable

Remarks

N/A

3.2.2.37. ADS/PCS arbitration status

Arbitration status

Value Description Remarks 0 No Request 1 ADS ADS 2 PCS PCS Brake or PCS Brake Hold 3 Invalid value

Remarks

-   -   When acceleration requested by PCS system in VP is smaller than         one requested by ADS, the status is set as “PCS”.     -   When acceleration requested by PCS system in VP is larger than         one requested by ADS, the status is set as “ADS”.

3.3. APIs for BODY control

3.3.1. API List for BODY control

3.3.1.1. Inputs

TABLE 6 Input APIs for BODY Control Signal Name Description Redundancy Turnsignal command Command to control the turnsignallight mode of N/A the vehicle platform Headlight command Command to control the headlight mode of the N/A vehicle platform Hazardlight command Command to control the hazardlight mode of the N/A vehicle platform Horn pattern command Command to control the pattern of horn ON-time N/A and OFF-time per cycle of the vehicle platform Horn cycle command Command to control the number of horn N/A ON/OFF cycles of the vehicle platform Continuous horn command Command to control of horn ON of the vehicle N/A platform Front windshield wiper command Command to control the front windshield wiper N/A of the vehicle platform Rear windshield wiper command Command to control the rear windshield wiper N/A mode of the vehicle platform HVAC (1st row) operation Command to start/stop 1st row air conditioning N/A command control HVAC (2nd row) operation Command to start/stop 2nd row air conditioning N/A command control Target temperature (1st left) Command to set the target temperature around N/A command front left area Target temperature (1st right) Command to set the target temperature around N/A command front right area Target temperature (2nd left) Command to set the target temperature around N/A command rear left area Target temperature (2nd right) Command to set the target temperature around N/A command rear right area HVAC fan (1st row) command Command to set the fan level on the front AC N/A HVAC fan (2nd row) command Command to set the fan level on the rear AC N/A Air outlet (1st row) command Command to set the mode of 1st row air outlet N/A Air outlet (2nd row) command Command to set the mode of 2nd row air outlet N/A Air recirculation command Command to set the air recirculation mode N/A AC mode command Command to set the AC mode N/A

3.3.1.2. Outputs

TABLE 7 Output APIs for BODY Control Signal Name Description Redundancy Turnsignal status Status of the current turnsignallight N/A mode of the vehicle platform Headlight status Status of the current headlight mode of N/A the vehicle platform Hazardlight status Status of the current hazardlight mode N/A of the vehicle platform Horn status Status of the current horn of the vehicle N/A platform Front windshield wiper status Status of the current front windshield N/A wiper mode of the vehicle platform Rear windshield wiper status Status of the current rear windshield N/A wiper mode of the vehicle platform HVAC (1st row) status Status of activation of the 1^(st) row HVAC N/A HVAC (2nd row) status Status of activation of the 2^(nd) row HVAC N/A Target temperature (1st left) Status of set temperature of 1^(st) row left N/A status Target temperature (1st right) Status of set temperature of 1^(st) row right N/A status Target temperature (2nd left) Status of set temperature of 2^(nd) row left N/A status Target temperature (2nd right) Status of set temperature of 2^(nd) row N/A status right HVAC fan (1st row) status Status of set fan level of 1^(st) row N/A HVAC fan (2nd row) status Status of set fan level of 2^(nd) row N/A Air outlet (1st row) status Status of mode of 1st row air outlet N/A Air outlet (2nd row) status Status of mode of 2nd row air outlet N/A Air recirculation status Status of set air recirculation mode N/A AC mode status Status of set AC mode N/A Seat occupancy (1st right) Seat occupancy status in 1st right seat N/A status Seat belt (1st left) status Status of driver’s seat belt buckle switch N/A Seat belt (1st right) status Status of passenger’s seat belt buckle N/A switch Seat belt (2nd left) status Seat belt buckle switch status in 2nd left N/A seat Seat belt (2nd right) status Seat belt buckle switch status in 2nd N/A right seat Seat belt (3rd left) status Seat belt buckle switch status in 3rd left N/A seat Seat belt (3rd center) status Seat belt buckle switch status in 3rd N/A center seat Seat belt (3rd right) status Seat belt buckle switch status in 3rd N/A right seat

3.3.2. Details of Each API for BODY Control

3.3.2.1. Turnsignal command

Request to control turn-signal

Values

Value Description Remarks 0 OFF 1 Right Right blinker ON 2 Left Left blinker ON 3 Reserved

Remarks

-   -   N/A

3.3.2.2. Headlight command

Request to control headlight

Values

Value Description Remarks 0 No Request Keep current mode 1 TAIL mode request Side lamp mode 2 HEAD mode request Lo mode 3 AUTO mode request Auto mode 4 HI mode request Hi mode 5 OFF Mode Request 6-7 Reserved

Remarks

-   -   This command is valid when headlight mode on the combination         switch=“OFF” or “Auto mode=ON.”     -   Driver operation overrides this command.

3.3.2.3. Hazardlight command

Request to control hazardlight

Value Description Remarks 0 No Request 1 ON

Remarks

-   -   Driver operation overrides this command.     -   Hazardlight is ON while receiving “ON” command.

3.3.2.4. Horn pattern command

Request to choose a pattern of ON-time and OFF-time per cycle

Values

Value Description Remarks 0 No request 1 Pattern 1 ON-time: 250 ms OFF-time: 750 ms 2 Pattern 2 ON-time: 500 ms OFF-time: 500 ms 3 Pattern 3 Reserved 4 Pattern 4 Reserved 5 Pattern 5 Reserved 6 Pattern 6 Reserved 7 Pattern 7 Reserved

Remarks

N/A

3.3.2.5. Horn cycle command

Request to choose the number of ON and OFF cycles

Values

0 to 7 [−]

Remarks

N/A

3.3.2.6. Continuous horn command

Request to turn on/off horn

Values

Value Description Remarks 0 No request 1 ON

Remarks

-   -   This command's priority is higher than 3.3.2.4 Horn pattern and         3.3.2.5 Horn cycle command.     -   Horn is “ON” while receiving “ON” command.

3.3.2.7. Front windshield wiper command Request to control front windshield wiper

Values

Value Description Remarks 0 OFF mode request 1 Lo mode request 2 Hi mode request 3 Intermittent mode request 4 Auto mode request 5 Mist mode request One-time wiping 6,7 Reserved

Remarks

-   -   This command is valid when front windshield wiper mode on a         combination switch is “OFF” or “AUTO”.     -   Driver input overrides this command.     -   Windshieldwiper mode is kept while receiving a command.     -   Wiping speed of intermittent mode is fixed.

3.3.2.8. Rear windshield wiper command

Request to control rear windshield wiper

Values

Value Description Remarks 0 OFF mode request 1 Lo mode request 2 Reserved 3 Intermittent mode request 4-7 Reserved

Remarks

-   -   Driver input overrides this command     -   Windshieldwiper mode is kept while receiving a command.     -   Wiping speed of intermittent mode is fixed.

3.3.2.9. HVAC (1st row) operation command Request to start/stop 1st row air conditioning control

Values

Value Description Remarks 0 No request 1 ON 2 OFF

Remarks

-   -   N/A

3.3.2.10. HVAC (2nd row) operation command

Request to start/stop 2nd row air conditioning control

Values

Value Description Remarks 0 No request 1 ON 2 OFF

Remarks

-   -   N/A

3.3.2.11. Target temperature (1st left) command

Request to set target temperature in front left area

Values

Value Description Remarks 0 No request 60 to 85 [unit: ° F.] (by 1.0° F.) Target temperature

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.12. Target temperature (1st right) command

Request to set target temperature in front right area

Values

Value Description Remarks 0 No request 60 to 85 [unit: ° F.] (by 1.0° F.) Target temperature

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.13. Target temperature (2nd left) command

Request to set target temperature in rear left area

Values

Value Description Remarks 0 No request 60 to 85 [unit: ° F.] (by 1.0° F.) Target temperature

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.         3.3.2.14. Target temperature (2nd right) command

Request to set target temperature in rear right area

Values

Value Description Remarks 0 No request 60 to 85 [unit: ° F.] (by 1.0° F.) Target temperature

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.15. HVAC fan (1st row) command

Request to set fan level of front AC

Values

Value Description Remarks 0 No request 1 to 7 (Maximum) Fan level

Remarks

-   -   If you would like to turn the fan level to 0 (OFF), you should         transmit “HVAC (1st row) operation command=OFF.”     -   If you would like to turn the fan level to AUTO, you should         transmit “HVAC (1st row) operation command=ON.”

3.3.2.16. HVAC fan (2nd row) command

Request to set fan level of rear AC

Values

Value Description Remarks 0 No request 1 to 7 (Maximum) Fan level

Remarks

-   -   If you would like to turn the fan level to 0 (OFF), you should         transmit “HVAC (2nd row) operation command=OFF.”     -   If you would like to turn the fan level to AUTO, you should         transmit “HVAC (2nd row) operation command=ON.”

3.3.2.17. Air outlet (1st row) command

Request to set 1st row air outlet mode

Values

Value Description Remarks 0 No Operation 1 UPPER Air flows to upper body 2 U/F Air flows to upper body and feet 3 FEET Air flows to feet 4 F/D Air flows to feet and windshield defogger

Remarks

-   -   N/A

3.3.2.18. Air outlet (2nd row) command

Request to set 2nd row air outlet mode

Values

Value Description Remarks 0 No Operation 1 UPPER Air flows to upper body 2 U/F Air flows to the upper body and feet 3 FEET Air flows to feet.

Remarks

-   -   N/A

3.3.2.19. Air recirculation command

Request to set air recirculation mode

Values

Value Description Remarks 0 No request 1 ON 2 OFF

Remarks

-   -   N/A

3.3.2.20. AC mode command

Request to set AC mode

Values

Value Description Remarks 0 No request 1 ON 2 OFF

Remarks

-   -   N/A

3.3.2.21. Turnsignal status

Values

Value Description Remarks 0 OFF 1 Left 2 Right 3 Invalid

Remarks

N/A

3.3.2.22. Headlight status

Values

Value Description Remarks 0 OFF 1 TAIL 2 Lo 3 Reserved 4 Hi 5-6 Reserved 7 Invalid

Remarks

N/A

3.3.2.23. Hazardlight status

Values

Value Description Remarks 0 OFF 1 Hazard 2 Reserved 3 Invalid

Remarks

N/A

3.3.2.24. Horn status

Values

Value Description Remarks 0 OFF 1 ON 2 Reserved 3 Invalid

Remarks

In the case that 3.3.2.4 the Horn Pattern Command is active, the Horn status is “1” even if there are OFF periods in some patterns.

3.3.2.25. Front windshield wiper status

Values

Value Description Remarks 0 OFF 1 Lo 2 Hi 3 INT 4-5 Reserved 6 Fail 7 Invalid

Remarks

N/A

3.3.2.26. Rear windshield wiper status

Values

Value Description Remarks 0 OFF 1 Lo 2 Reserved 3 INT 4-5 Reserved 6 Fail 7 Invalid

Remarks

N/A

3.3.2.27. HVAC (1st row) status

Values

Value Description Remarks 0 OFF 1 ON

Remarks

-   -   N/A

3.3.2.28. HVAC (2nd row) status

Values

Value Description Remarks 0 OFF 1 ON

Remarks

-   -   N/A

3.3.2.29. Target Temperature (1st left) status

Values

Value Description Remarks  0 Lo Max cold 60 to 85 [unit: ° F.] Target temperature 100 Hi Max hot FFh Unknown

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.30. Target Temperature (1st right) status

Values

Value Description Remarks  0 Lo Max cold 60 to 85 [unit: ° F.] Target temperature 100 Hi Max hot FFh Unknown

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.31. Target Temperature (2nd left) status

Values

Value Description Remarks 0 Lo Max cold 60 to 85 [unit: ° F.] Target temperature 100 Hi Max hot FFh Unknown

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.32. Target Temperature (2nd right) status

Values

Value Description Remarks 0 Lo Max cold 60 to 85 [unit: ° F.] Target temperature 100 Hi Max hot FFh Unknown

Remarks

-   -   In case ° C. is used in VP, value should be set as ° C.

3.3.2.33. HVAC fan (1st row) status

Values

Value Description Remarks 0 OFF 1 to 7 Fan Level 8 Undefined

Remarks

-   -   N/A

3.3.2.34. HVAC fan (2nd row) status

Values

Value Description Remarks 0 OFF 1 to 7 Fan Level 8 Undefined

Remarks

-   -   N/A

3.3.2.35. Air outlet (1st row) status

Values

Value Description Remarks 0 ALL OFF 1 UPPER Air flows to upper body 2 U/F Air flows to upper body and feet 3 FEET Air flows to feet. 4 F/D Air flows to feet and windshield defogger operates 5 DEF Windshield defogger 7 Undefined

Remarks

-   -   N/A

3.3.2.36. Air outlet (2nd row) status

Values

Value Description Remarks 0 ALL OFF 1 UPPER Air flows to upper body 2 U/F Air flows to upper body and feet 3 FEET Air flows to feet. 7 Undefined

Remarks

-   -   N/A

3.3.2.37. Air recirculation status

Values

Value Description Remarks 0 OFF 1 ON

Remarks

-   -   N/A

3.3.2.38. AC mode status

Values

Value Description Remarks 0 OFF 1 ON

Remarks

-   -   N/A

3.3.2.39. Seat occupancy (1st right) status

Values

Value Description Remarks 0 Not occupied 1 Occupied 2 Undecided In case of IG OFF or communication disruption to seat sensor 3 Failed

Remarks

-   -   When there is luggage on the seat, this signal may be set as         “Occupied”.

3.3.2.40. Seat belt (1st left) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Fault of a switch

Remarks

N/A

3.3.2.41. Seat belt (1st right) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Fault of a switch

Remarks

N/A

3.3.2.42. Seat belt (2nd left) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Reserved

Remarks

-   -   cannot detect sensor failure

3.3.2.43. Seat belt (2nd right) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Reserved

Remarks

-   -   cannot detect sensor failure

3.3.2.44. Seat belt (3rd left) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Reserved

Remarks

-   -   cannot detect sensor failure

3.3.2.45. Seat belt (3rd center) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Reserved

Remarks

-   -   cannot detect sensor failure

3.3.2.46. Seat belt (3rd right) status

Values

Value Description Remarks 0 Buckled 1 Unbuckled 2 Undetermined In case where sensor does not work just after IG-ON 3 Reserved

Remarks

-   -   cannot detect sensor failure

3.4. APIs for Power control

3.4.1. API List for Power control

3.4.1.1. Inputs

TABLE 8 Input APIs for Power control Signal Name Description Redundancy Power mode Command to control the N/A command power mode of VP

3.4.1.2. Outputs

TABLE 9 Output APIs for Power control Signal Name Description Redundancy Power mode status Status of the current power mode of VP N/A

3.4.2. Details of each API for Power control 3.4.2.1. Power mode command

Request to control power mode

Values

Value Description Remarks 0 No request 1 Sleep Turns OFF the vehicle 2 Wake Turns ON VCIB 3 Reserved Reserved for data expansion 4 Reserved Reserved for data expansion 5 Reserved Reserved for data expansion 6 Drive Turns ON the vehicle

Remarks

-   -   The state machine diagram of the power modes is shown in FIG. 12         .

[Sleep]

Vehicle power off condition. In this mode, the main battery does not supply power to each system, and neither VCIB nor other VP ECUs are activated.

[Wake]

VCIB is awake by the auxiliary battery. In this mode, ECUs other than VCIB are not awake except for some of the body electrical ECUs.

[Driving Mode]

Vehicle power on condition. In this mode, the main battery supplies power to the whole VP and all the VP ECUs including VCIB are awake.

3.4.2.2. Power mode status

Values

Value Description Remarks 0 Reserved 1 Sleep 2 Wake 3 Reserved 4 Reserved 5 Reserved 6 Drive 7 Unknown means unhealthy situation would occur

Remarks

-   -   VCIB will transmit [Sleep] as Power Mode Status continuously for         3000 [ms] after executing the sleep sequence. And then, VCIB         will shut down.     -   ADS should stop transmitting signals to VCIB while VCIB is         transmitting [Sleep].

3.5. APIs for Failure Notification

3.5.1. API List for Failure Notification

3.5.1.1. Inputs

TABLE 10 Input APIs for Failure Notification Signal Name Description Redundancy N/A N/A N/A

3.5.1.2. Outputs

TABLE 11 Output APIs for Failure Notification Signal Name Description Redundancy Request for ADS operation Applied Impact detection signal N/A Performance deterioration of Applied brake system Performance deterioration of N/A propulsion system Performance deterioration of shift N/A control system Performance deterioration of Applied immobilization system Performance deterioration of Applied steering system Performance deterioration of Applied power supply system Performance deterioration of Applied communication system

3.5.2. Details of each API for Failure Notification

3.5.2.1. Request for ADS Operation

Values

Value Description Remarks 0 No request 1 Need maintenance 2 Need to be back to garage 3 Need to stop immediately Others Reserved

Remarks

-   -   This signal shows a behavior which the ADS is expected to do         according to a failure which happened in the VP.

3.5.2.2. Impact detection signal

Values

Value Description Remarks 0 Normal 5 Crash detection with activated airbag 6 Crash detection with shut off high voltage circuit 7 Invalid value Others Reserved

Remarks

-   -   When the event of crash detection is generated, the signal is         transmitted 50 consecutive times every 100 [ms]. If the crash         detection state changes before the signal transmission is         completed, the high signal of priority is transmitted.

Priority: crash detection>normal

-   -   Transmits for 5 s regardless of ordinary response at crash,         because the vehicle breakdown judgment system shall be sent a         voltage OFF request for 5 s or less after crash in HV vehicle.

Transmission interval is 100 ms within fuel cutoff motion delay allowance time (1 s) so that data can be transmitted more than 5 times.

In this case, an instantaneous power interruption is taken into account.

3.5.2.3. Performance deterioration of brake system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.5.2.4. Performance deterioration of propulsion system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.5.2.5. Performance deterioration of shift control system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.5.2.6. Performance deterioration of immobilization system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.5.2.7. Performance deterioration of Steering system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.5.2.8. Performance deterioration of power supply system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.5.2.9. Performance deterioration of communication system

Values

Value Description Remarks 0 Normal — 1 Deterioration detected —

Remarks

-   -   N/A

3.6. APIs for Security

3.6.1. API List for Security

3.6.1.1. Inputs

TABLE 12 Input APIs for Security Signal Name Description Redundancy Door Lock (front) command Command to control both 1st doors lock N/A Door Lock (rear) command Command to control both 2nd doors N/A and trunk lock Central door lock command Command to control the all door lock N/A Device Authentication This is the 8th byte from the 1st byte of N/A Signature the 1st word the Signature value. Device Authentication This is the 16th byte from the 9th byte N/A Signature the 2nd word of the Signature value. Device Authentication This is the 24th byte from the 17th byte N/A Signature the 3rd word of the Signature value. Device Authentication This is the 32th byte from the 25th byte N/A Signature the 4th word of the Signature value.

3.6.1.2. Outputs

TABLE 13 Output APIs for Security Signal Name Description Redundancy Door lock (1st left) status Status of the current 1st-left door lock N/A Door lock (1st right) status Status of the current 1st-right door lock N/A Door lock (2nd left) status Status of the current 2nd-left door lock N/A Door lock (2nd right) status Status of the current 2nd-right door lock N/A Trunk Lock status Status of the current trunk (back door) N/A lock Central door lock status Status of the current all door lock N/A Alarm system status Status of the current vehicle alarm N/A Device Authentication Seed the This is the 8th byte from the 1st byte of N/A 1st word the Seed value. Device Authentication Seed the This is the 16th byte from the 9th byte of N/A 2nd word the Seed value. Trip Counter This counter is incremented in units of N/A trips by the Freshness Value management master ECU. Reset Counter This counter is incremented periodically N/A by the Freshness Value management master ECU. 1st Left Door Open Status Status of the current 1st-left door N/A open/close of the vehicle platform 1st Right Door Open Status Status of the current 1st-right door N/A open/close of the vehicle platform 2nd Left Door Open Status Status of the current 2nd-left door N/A open/close of the vehicle platform 2nd Right Door Open Status Status of the current 2nd-right door N/A open/close of the vehicle platform Trunk Status Status of the current trunk door open of N/A the vehicle platform Hood Open Status Status of the current hood open/close of N/A the vehicle platform

3.6.2. Details of Each API for Security

3.6.2.1. Door Lock (front) command, Door Lock (rear) command

Values

Value Description Remarks 0 No Request 1 Lock Not supported in Toyota VP 2 Unlock 3 Reserved

Remarks

-   -   If ADK requests for unlocking front side, both front doors are         unlocked.     -   If ADK requests for unlocking rear side, both 2nd row and trunk         doors are unlocked.     -   If ADK requests for locking any door, it should use “Central         door lock command.”

(The functionality for individual locking is not supported in Toyota VP.)

3.6.2.2. Central door lock command

Request to control all doors' lock

Values

Value Description Remarks 0 No Request 1 Lock (all) 2 Unlock (all) 3 Reserved

Remarks

-   -   N/A

3.6.2.3. Device Authentication Signature the 1st word, Device Authentication Signature the 2nd word, Device Authentication Signature the 3rd word, Device Authentication Signature the 4th word, Device Authentication Seed the 1st word, Device Authentication Seed the 2nd word

Device Authentication Signature the 1st word is presented in from 1st to 8th bytes of the signature.

Device Authentication Signature the 2nd word is presented in from 9th to 16th bytes of the signature.

Device Authentication Signature the 3rd word is presented in from 17th to 24th bytes of the signature.

Device Authentication Signature the 4th word is presented in from 25th to 32nd bytes of the signature.

Device Authentication Seed the 1st word is presented in from 1st to 8th bytes of the seed.

Device Authentication Seed the 2nd word is presented in from 9th to 16th bytes of the seed.

3.6.2.4. Door lock (1st left) status

Values

Value Description Remarks 0 Reserved 1 Locked 2 Unlocked 3 Invalid

Remarks

-   -   N/A

3.6.2.5. Door lock (1st right) status

Values

Value Description Remarks 0 Reserved 1 Locked 2 Unlocked 3 Invalid

Remarks

-   -   N/A

3.6.2.6. Door lock (2nd left) status

Values

Value Description Remarks 0 Reserved 1 Locked 2 Unlocked 3 Invalid

Remarks

-   -   N/A

3.6.2.7. Door lock (2nd right) status

Values

Value Description Remarks 0 Reserved 1 Locked 2 Unlocked 3 Invalid

Remarks

-   -   N/A

3.6.2.8. Door lock status of all doors

Values

Value Description Remarks 0 Reserved 1 All Locked 2 Anything Unlocked 3 Invalid

Remarks

-   -   In case any doors are unlocked, “Anything Unlocked.”     -   In case all doors are locked, “All Locked.”

3.6.2.9. Alarm system status

Values

Value Description Remarks 0 Disarmed Alarm System is not activated. 1 Armed Alarm System is activated without alarming. 2 Active Alarm System is activated, and the alarm is beeping. 3 Invalid

Remarks

N/A

3.6.2.9.1. Trip Counter

This counter is incremented in a unit of trips by the Freshness Value management master ECU.

Values

0—FFFFh

Remarks

-   -   This value is used to create a Freshness value.     -   For details, please refer to the other material [the         specification of Toyota's MAC module].

3.6.2.9.2. Reset Counter

This counter is incremented periodically by the Freshness Value management master ECU.

Values

0—FFFFFh

Remarks

-   -   This value is used to create a Freshness value.     -   For details, please refer to the other material [the         specification of Toyota's MAC module].

3.6.2.10. 1st Left Door Open Status

Status of the current 1st-left door open/close of the vehicle platform

Values

Value Description Remarks 0 Reserved 1 Open 2 Closes 3 Invalid

Remarks

N/A

3.6.2.11. 1st Right Door Open Status

Status of the current 1st-right door open/close

Values

Value Description Remarks 0 Reserved 1 Open 2 Close 3 Invalid

Remarks

N/A

3.6.2.12. 2nd Left Door Open Status

Status of the current 2nd-left door open/close

Values

Value Description Remarks 0 Reserved 1 Open 2 Close 3 Invalid

Remarks

N/A

3.6.2.13. 2nd Right Door Open Status

Status of the current 2nd-right door open/close

Values

Value Description Remarks 0 Reserved 1 Open 2 Close 3 Invalid

Remarks

N/A

3.6.2.14. Trunk Status

Status of the current trunk door open/close

Values

Value Description Remarks 0 Reserved 1 Open 2 Close 3 Invalid

Remarks

N/A

3.6.2.15. Hood Open Status

Status of the current hood open/close

Values

Value Description Remarks 0 Reserved 1 Open 2 Close 3 Invalid

Remarks

N/A

4. API Guides to control Toyota Vehicles

This section shows in detail the way of using APIs for Toyota vehicles.

4.1. APIs for Vehicle Motion Control

4.1.1. API List for Vehicle Motion Control

Input and output APIs for vehicle motion control are shown in Table 14 and Table 15, respectively. Usage guides of some APIs are presented in the following sections as indicated in each table.

4.1.1.1. Inputs

TABLE 14 Input APIs for Vehicle Motion Control Usage Signal Name Description Redundancy Guide Propulsion Direction Request for shift change N/A 4.1.2.1 Command from/to forward (D range) to/from back (R range) Immobilization Request for turning on/off Applied 4.1.2.2 Command Wheel Lock Standstill Command Request for keeping on/off Applied 4.1.2.3 stationary Acceleration Request for Applied 4.1.2.1 Command acceleration/deceleration 4.1.2.2 4.1.2.3 4.1.2.4 Front Wheel Steer Request for front wheel steer Applied 4.1.2.5 Angle Command angle Vehicle Mode Request for changing from/to Applied 4.1.2.6 Command manual mode to/from Autonomous Mode High Dynamics Request for increasing braking Applied — Command response performance* *Reaction time in VP upon a request from ADK

4.1.1.2. Outputs

TABLE 15 Output APIs for Vehicle Motion Control Usage Signal Name Description Redundancy Guide Propulsion Direction Status Current shift status N/A   Immobilization Status Status of immobilization (e.g. EPB and Shift P) Applied 4.1.2.2 4.1.2.3 Standstill Status Standstill status N/A 4.1.2.3 Estimated Gliding Acceleration Estimated vehicle acceleration/deceleration when N/A — throttle is fully closed Estimated maximum acceleration Estimated maximum acceleration Applied — Estimated maximum deceleration Estimated maximum deceleration Applied — Front wheel steer angle Front wheel steer angle Applied 4.1.2.5 Front wheel steer angle rate Front wheel steer angle rate Applied — Front wheel steer angle rate Road wheel angle rate limit Applied — limitation Estimated maximum lateral Estimated max lateral acceleration Applied — acceleration Estimated maximum lateral Estimated max lateral acceleration rate Applied — acceleration rate Intervention of accelerator pedal This signal shows whether the accelerator pedal is N/A 4.1.2.4 depressed by a driver (intervention) Intervention of brake pedal This signal shows whether the brake pedal is N/A — depressed by a driver (intervention) Intervention of steering wheel This signal shows whether the steering wheel is N/A 4.1.2.5 turned by a driver (intervention) Intervention of shift lever This signal shows whether the shift lever is N/A — controlled by a driver (intervention) Wheel speed pulse (front left) Pulse from wheel speed sensor (Front Left Wheel) N/A — Wheel rotation direction (front left) Rotation direction of wheel (Front Left) N/A — Wheel speed pulse (front right) Pulse from wheel speed sensor (Front Right N/A — Wheel) Wheel rotation direction (front right) Rotation direction of wheel (Front Right) N/A — Wheel speed pulse (rear left) Pulse from wheel speed sensor (Rear Left Wheel) Applied — Wheel rotation direction (Rear left) Rotation direction of wheel (Rear Left) Applied — Wheel speed pulse (rear right) Pulse from wheel speed sensor (Rear Right Applied — Wheel) Wheel rotation direction (Rear right) Rotation direction of wheel (Rear Right) Applied — Traveling direction Moving direction of vehicle Applied 4.1.2.1 4.1.2.3 Vehicle velocity Estimated longitudinal velocity of vehicle Applied 4.1.2.2 Longitudinal acceleration Estimated longitudinal acceleration of vehicle Applied — Lateral acceleration Sensor value of lateral acceleration of vehicle Applied — Yawrate Sensor value of Yaw rate Applied — Slipping Detection Detection of tire glide/spin/skid Applied — Vehicle mode state State of whether Autonomous Mode, manual mode Applied 4.1.2.6 or others Readiness for autonomization Situation of whether the vehicle can transition to Applied 4.1.2.6 Autonomous Mode or not Failure status of VP functions for This signal is used to show whether VP functions Applied — Autonomous Mode have some failures mode when a vehicle works as Autonomous Mode. PCS Alert Status Status of PCS (Alert) N/A — PCS Preparation Status Status of PCS (Prefill) N/A — PCS Brake/PCS Brake Hold Status Status of PCS (PB/PBH) N/A — ADS/PCS arbitration status ADS/PCS arbitration status N/A —

4.1.2. API guides in Details for Vehicle Motion Control

4.1.2.1. Propulsion Direction Command

Please refer to 3.2.2.1 for value and remarks in detail.

FIG. 13 shows shift change sequences in detail.

First deceleration is requested by Acceleration Command and the vehicle is stopped. When Traveling direction is set to “standstill”, any shift position can be requested by Propulsion Direction Command. (In FIG. 13 , “D” “R”).

Deceleration has to be requested by Acceleration Command until completing shift change.

After shift position is changed, acceleration/deceleration can be chosen based on Acceleration Command.

While Vehicle mode state=Autonomous Mode, driver's shift lever operation is not accepted.

4.1.2.2. Immobilization Command

Please refer to 3.2.2.2 for value and remarks in detail.

FIG. 14 shows how to activate/deactivate immobilization function.

Deceleration is requested with Acceleration Command to make a vehicle stop. When Vehicle velocity goes to zero, Immobilization function is activated by Immobilization Command=“Applied”. Acceleration Command is set to Deceleration until Immobilization Status is set to “Applied”.

When deactivating Immobilization function, Immobilization Command=“Released” has to be requested and simultaneously Acceleration Command has to be set as deceleration until confirming Immobilization Status=“Released”.

After Immobilization function is deactivated, the vehicle can be accelerated/decelerated based on Acceleration Command.

4.1.2.3. Standstill Command

Please refer to 3.2.2.3 for value and remarks in detail.

In case where Standstill Command is set as “Applied”, brakehold function can be ready to be used and brakehold function is activated in a condition where a vehicle stops and Acceleration Command is set as Deceleration (<0). And then Standstill Status is changed to “Applied”. On the other hand, in case where Standstill Command is set as “Released”, brakehold function is deactivated.

FIG. 15 shows standstill sequences.

To make a vehicle stop, deceleration is requested with Acceleration Command.

When the vehicle stops for a while, Traveling direction is changed to “standstill”. Even during Standstill status=“Applied”, deceleration shall be requested with Acceleration Command.

If you want the vehicle to move forward, Acceleration Command is set as Acceleration (>0). Then brake hold function is released and the vehicle is accelerated.

4.1.2.4. Acceleration Command

Please refer to 3.2.2.4 for value and remarks in detail.

The below shows how a vehicle behaves when an acceleration pedal is operated.

In case where the accelerator pedal is operated, a maximum acceleration value of either 1) one calculated from accelerator pedal stroke or 2) Acceleration Command input from ADK is chosen. ADK can see which value is selected by checking Intervention of accelerator pedal.

The below shows how a vehicle behaves when a brake pedal is operated.

Deceleration value in the vehicle is the sum of 1) one calculated from the brake pedal stroke and 2) one requested from ADK.

4.1.2.5. Front Wheel Steer Angle Command

Please refer to 3.2.2.5 for value and remarks in detail.

The below shows the way of using Front Wheel Steer Angle Command.

Front Wheel Steer Angle Command is set as a relative value from Front wheel steer angle.

For example, in case where Front wheel steer angle=0.1 [rad] and a vehicle goes straight;

If ADK would like to go straight, Front Wheel Steer Angle Command should be set to 0+0.1=0.1[rad].

If ADK requests to steer by −0.3 [rad], Front Wheel Steer Angle Command should be set to −0.3+0.1=−0.2 [rad].

The below shows how a vehicle behaves when a driver operates the steering.

A maximum value is selected either from 1) one calculated from steering wheel operation by the driver or 2) one requested by ADK.

Note that Front Wheel Steer Angle Command is not accepted if the driver strongly operates the steering wheel. This situation can be found by Intervention of steering wheel flag.

4.1.2.6. Vehicle Mode Command

The state machine of mode transition for Autono-MaaS vehicle is shown in FIG. 16 .

The explanation of each state is shown as follows.

State Description Manual A vehicle begins with this state and is under a control of a human driver. ADK cannot give any controls (except some commands) to VP. Power mode status and Vehicle mode state are in the followings: Power mode status = Wake or Drive Vehicle mode state = Manual Mode Autonomy ADK can communicate to VP after authentication is successful. VP is under the control of the ADK as a result of being issued “Request for Autonomy.” Power mode status and Vehicle mode state are in the followings: Power mode status = Drive Vehicle mode state = Autonomous Mode

The explanation of each transition is shown as follows.

Transition Conditions a When the following conditions are established, the mode will be transitioned from Manual to Autonomy: The ADK is authenticated, Power mode status = Drive, Readiness for autonomization = Ready For Autonomy Vehicle Mode Command = Request For Autonomy. b When the following conditions are established, the mode will be transitioned from Autonomy to Manual: Vehicle Mode Command = Deactivation Request.

4.2. APIs for BODY Control

4.2.1. API List for BODY Control

4.2.1.1. Inputs

TABLE 16 Input APIs for BODY Control Signal Name Description Redundancy Usage Guide Turnsignal command Command to control the N/A — turnsignallight mode of the vehicle platform Headlight command Command to control the headlight N/A — mode of the vehicle platform Hazardlight command Command to control the hazardlight N/A — mode of the vehicle platform Horn pattern command Command to control the pattern of N/A — horn ON-time and OFF-time per cycle of the vehicle platform Horn cycle command Command to control the number of N/A — horn ON/OFF cycles of the vehicle platform Continuous horn command Command to control of horn ON of N/A — the vehicle platform Front windshield wiper Command to control the front N/A — command windshield wiper of the vehicle platform Rear windshield wiper Command to control the rear N/A — command windshield wiper mode of the vehicle platform HVAC (1st row) operation Command to start/stop 1st row air N/A — command conditioning control HVAC (2nd row) operation Command to start/stop 2nd row air N/A — command conditioning control Target temperature (1st left) Command to set the target N/A — command temperature around front left area Target temperature (1st right) Command to set the target N/A — command temperature around front right area Target temperature (2nd left) Command to set the target N/A — command temperature around rear left area Target temperature (2nd right) Command to set the target N/A — command temperature around rear right area HVAC fan (1st row) command Command to set the fan level on the N/A — front AC HVAC fan (2nd row) command Command to set the fan level on the N/A — rear AC Air outlet (1st row) command Command to set the mode of 1 st N/A — row air outlet Air outlet (2nd row) command Command to set the mode of 2nd N/A — row air outlet Air recirculation command Command to set the air recirculation N/A — mode AC mode command Command to set the AC mode N/A  

4.2.1.2. Outputs

TABLE 17 Output APIs for BODY Control Signal Name Description Redundancy Usage Guide Turnsignal status Status of the current turnsignallight N/A — mode of the vehicle platform Headlight status Status of the current headlight mode of N/A — the vehicle platform Hazardlight status Status of the current hazardlight mode of N/A — the vehicle platform Horn status Status of the current horn of the vehicle N/A — platform Front windshield wiper Status of the current front windshield N/A — status wiper mode of the vehicle platform Rear windshield wiper Status of the current rear windshield N/A — status wiper mode of the vehicle platform HVAC (1st row) status Status of activation of the 1^(st) row HVAC N/A — HVAC (2nd row) status Status of activation of the 2^(nd) row N/A — HVAC Target temperature (1st Status of set temperature of 1^(st) row left N/A — left) status Target temperature (1st Status of set temperature of 1^(st) row right N/A — right) status Target temperature (2nd Status of set temperature of 2^(nd) row left N/A — left) status Target temperature (2nd Status of set temperature of 2^(nd) row right N/A — right) status HVAC fan (1st row) status Status of set fan level of 1 st row N/A — HVAC fan (2nd row) Status of set fan level of 2^(nd) row N/A — status Air outlet (1st row) status Status of mode of 1st row air outlet N/A — Air outlet (2nd row) status Status of mode of 2nd row air outlet N/A — Air recirculation status Status of set air recirculation mode N/A — AC mode status Status of set AC mode N/A — Seat occupancy (1st right) Seat occupancy status in 1st left seat N/A — status Seat belt (1st left) status Status of driver’s seat belt buckle switch N/A — Seat belt (1st right) status Status of passenger’s seat belt buckle N/A — switch Seat belt (2nd left) status Seat belt buckle switch status in 2nd left N/A — seat Seat belt (2nd right) status Seat belt buckle switch status in 2nd N/A — right seat

4.3. APIs for Power Control

4.3.1. API List for Power Control

4.3.1.1. Inputs

TABLE 18 Input APIs for Power Control Signal Name Description Redundancy Usage Guide Power mode command Command to control N/A — the power mode of VP

4.3.1.2. Outputs

TABLE 19 Output APIs for Power Control Signal Name Description Redundancy Usage Guide Power mode status Status of the current power N/A — mode of VP

4.4. APIs for Failure Notification

4.4.1. API List for Failure Notification

4.4.1.1. Inputs

TABLE 20 Input APIs for Failure Notification Signal Name Description Redundancy Usage guide N/A — — —

4.4.1.2. Outputs

TABLE 21 Output APIs for Failure Notification Signal Name Description Redundancy Usage guide Request for ADS Operation — Applied — Impact detection signal — N/A — Performance deterioration of Brake — Applied — system Performance deterioration of Propulsion — N/A — system Performance deterioration of Shift — N/A — control system Performance deterioration of — Applied — Immobilization system Performance deterioration of Steering Applied — system Performance deterioration of Power Applied — supply system Performance deterioration of Applied — Communication system

4.5. APIs for Security

4.5.1. API List for Security

Input and output APIs for Security are shown in Table 22 and Table 23, respectively. Usage guides of some APIs are presented in the following sections as indicated in each table.

4.5.1.1. Inputs

TABLE 22 Input APIs for Security Signal Name Description Redundancy Usage Guide Door Lock (front) Command to control 1st N/A — command both doors lock Door Lock (rear) Command to control 2nd N/A — command both doors and trunk lock Central door lock Command to control the N/A — command all door lock Device Authentication This is the 8th byte from N/A 4.5.2.1 Signature the 1st word the 1st byte of the Signature value. Device Authentication This is the 16th byte N/A 4.5.2.1 Signature the 2nd word from the 9th byte of the Signature value. Device Authentication This is the 24th byte N/A 4.5.2.1 Signature the 3rd word from the 17th byte of the Signature value. Device Authentication This is the 32th byte N/A 4.5.2.1 Signature the 4th word from the 25th byte of the Signature value.

4.5.1.2. Outputs

TABLE 23 Output APIs for Security Signal Name Description Redundancy Usage Guide Door lock (1st left) Status of the current 1st-left N/A — status door lock Door lock (1st right) Status of the current 1st-right N/A — status door lock Door lock (2nd left) Status of the current 2nd-left N/A — status door lock Door lock (2nd right) Status of the current 2nd-right N/A — status door lock Central door lock Status of the current all door N/A — status lock Alarm system status Status of the current vehicle N/A — alarm Device Authentication This is the 8th byte from the N/A — Seed the 1 st word 1st byte of the Seed value. Device Authentication This is the 16th byte from the N/A — Seed the 2nd word 9th byte of the Seed value. Trip Counter This counter is incremented in N/A — units of trips by the Freshness Value management master ECU. Reset Counter This counter is incremented N/A — periodically by the Freshness Value management master ECU. 1st Left Door Open Status of the current 1st-left N/A — Status door open/close of the vehicle platform 1st Right Door Open Status of the current 1st-right N/A — Status door open/close of the vehicle platform 2nd Left Door Open Status of the current 2nd-left N/A — Status door open/close of the vehicle platform 2nd Right Door Open Status of the current 2nd-right N/A — Status door open/close of the vehicle platform Trunk Status Status of the current trunk door N/A — open of the vehicle platform Hood Open Status Status of the current hood N/A — open/close of the vehicle platform

4.5.2. API guides in Details for Security

4.5.2.1. Device Authentication Protocol

Device authentication is applied when the VCIB is activated from “Sleep” mode.

After the authentication succeeds, the VCIB can start to communicate with ADK.

Authentication process is as shown in FIG. 17 Authentication Process.

Authentication Specification

Item Specification Note Encryption algorithms AES FIPS 197 Key length 128 bit — Block cipher modes of operation CBC SP 800-38A Hash algorithms SHA-256 FIPS 180-4 Seed length 128 bit — Signature length 256 bit —

Though an embodiment of the present disclosure has been described, it should be understood that the embodiment disclosed herein is illustrative and non-restrictive in every respect. The scope of the present disclosure is defined by the terms of the claims and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims. 

What is claimed is:
 1. A vehicle on which an autonomous driving system is mountable, the vehicle comprising: a vehicle platform that carries out vehicle control in accordance with a command from the autonomous driving system, wherein the vehicle platform includes a base vehicle and a vehicle control interface box that interfaces between the autonomous driving system and the base vehicle, from the autonomous driving system to the base vehicle, a wheel steer angle command that requests a steer angle of a steering wheel is transmitted through the vehicle control interface box, from the base vehicle to the autonomous driving system, a signal indicating the steer angle is transmitted, and the steer angle requested in the wheel steer angle command is set not to exceed a restriction range of a rate of the steer angle that is set based on a velocity of the vehicle.
 2. The vehicle according to claim 1, wherein the restriction range is set such that magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a first velocity is smaller than magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a second velocity lower than the first velocity.
 3. A method of controlling a vehicle on which an autonomous driving system is mountable, the vehicle including a vehicle platform that carries out vehicle control in accordance with a command from the autonomous driving system, the vehicle platform including a base vehicle and a vehicle control interface box that interfaces between the autonomous driving system and the base vehicle, the method comprising: transmitting a wheel steer angle command that requests a steer angle of a steering wheel from the autonomous driving system to the base vehicle through the vehicle control interface box; transmitting a signal indicating the steer angle from the base vehicle to the autonomous driving system; and setting the steer angle requested in the wheel steer angle command not to exceed a restriction range of a rate of the steer angle that is set based on a velocity of the vehicle.
 4. The method of controlling a vehicle according to claim 3, wherein the restriction range is set such that magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a first velocity is smaller than magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a second velocity lower than the first velocity.
 5. A vehicle control interface box that interfaces between an autonomous driving system and a vehicle on which the autonomous driving system is mountable, the vehicle including a vehicle platform that carries out vehicle control in accordance with a command from the autonomous driving system, the vehicle platform including a base vehicle, wherein the vehicle control interface box transmits a wheel steer angle command that requests a steer angle of a steering wheel from the autonomous driving system to the base vehicle, and transmits a signal indicating the steer angle from the base vehicle to the autonomous driving system, and the steer angle requested in the wheel steer angle command is set not to exceed a restriction range of a rate of the steer angle that is set based on a velocity of the vehicle.
 6. The vehicle control interface box according to claim 5, wherein the restriction range is set such that magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a first velocity is smaller than magnitude of an upper limit value of the rate when the velocity of the vehicle is set to a second velocity lower than the first velocity. 